159661917 has 12 divisors (see below), whose sum is σ = 234974844. Its totient is φ = 104432640.

The previous prime is 159661897. The next prime is 159661927. The reversal of 159661917 is 719166951.

159661917 is a `hidden beast` number, since 15 + 9 + 6 + 619 + 17 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 136679481 + 22982436 = 11691^2 + 4794^2 .

It is not a de Polignac number, because 159661917 - 2²⁰ = 158613341 is a prime.

It is a super-2 number, since 2×159661917² = 50983855480229778, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159661927) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166884 + ... + 167837.

It is an arithmetic number, because the mean of its divisors is an integer number (19581237).

Almost surely, 2^159661917 is an apocalyptic number.

It is an amenable number.

159661917 is a deficient number, since it is larger than the sum of its proper divisors (75312927).

159661917 is a wasteful number, since it uses less digits than its factorization.

159661917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334780 (or 334777 counting only the distinct ones).

The product of its digits is 102060, while the sum is 45.

The square root of 159661917 is about 12635.7396696830. The cubic root of 159661917 is about 542.5008793264.

The spelling of 159661917 in words is "one hundred fifty-nine million, six hundred sixty-one thousand, nine hundred seventeen".